stuna -sun- gismu

x1 is to the east/eastern side of x2 according to frame of reference x3.

See also stici, berti, snanu, farna.

In notes:

berti
x1 is to the north/northern side [right-hand-rule pole] of x2 according to frame of reference x3.
farna
x1 is the direction of x2 (object/event) from origin/in frame of reference x3.
snanu
x1 is to the south/southern side of x2 according to frame of reference x3.
stici
x1 is to the west/western side of x2 according to frame of reference x3.
berstuna
x1 is northeast of x2 in frame of reference x3.
sunsicyjudri
j1 is the longitude/right ascension of j2 in system j3
sunxi'o
x1 is Orthodox Christian in aspect x2.
du'arna
x1 is to the east of x2 according to frame of reference x3.